Giving birth seems to slow the progression of multiple sclerosis (MS), suggests research published ahead of print in the Journal of Neurology Neurosurgery and Psychiatry.
To date, the evidence for whether childbirth is helpful or worsens the course of the disease has been inconclusive.
The Belgian researchers tracked disease progression in 330 women with MS for an average of 18 years between 2005 and 2007. All the women had been referred to one specialist centre, and had had their first symptoms from the ages of 22 to almost 38.
After an average of 18 years living with MS, over half of all the women (55%) were categorised as Expanded Disability Status Scale (EDSS) 6. This scale runs from 1 to 10, where 10 is death from MS. EDSS 6 refers to individual’s need for assistance with a cane, crutch, or brace to walk 100 metres.
Both the likelihood and speed of progression were affected by childbirth.
Women who had given birth to one or more children at any point in time before or after the start of symptoms were 34% less likely to progress to EDSS 6 than childless women.
Women whose children had been born after their MS began were 39% less likely to progress to EDSS 6 than women who had not had children. This held true even after taking account of the age at which symptoms began.
Women who had no children after their symptoms began progressed to EDSS 6 within 13 to 15 years, on average. But women who did have children then took an average of 22 to 23 years to reach this stage.
MS is a long term inflammatory disease of the central nervous system, and the authors suggest that sex hormones secreted during pregnancy may alter the body’s immune response and the extent of tissue damage, although it is not yet clear how.